I've got an application (okay, scratty PHP script) which glues together some API things and shows them onto a dashboard for me. Recently, I updated it to use Guzzle as the consuming client, since twitter now needs me to authenticate (I wrote about that if you're interested), and I used Composer to bring the new library in. It was very simple so I thought I'd share it as it's quite minimal example, and those are my favourite kind.

She includes a brief "getting started" for those not already familiar with Composer and shows a sample composer.json file that pulls in the Guzzle HTTP library. Then calling the "install" with Composer pulls in the files in the right place and all you have to do is add the needed require_once include to your autoloading process. Composer handles the rest.